U.S. patent application number 10/585243 was filed with the patent office on 2007-07-12 for method for producing hydrolyzable silicon group-containing oxyalkylene polymer and curing composition thereof.
Invention is credited to Hiroshi Iwakiri, Hidetoshi Odaka.
Application Number | 20070161768 10/585243 |
Document ID | / |
Family ID | 34823916 |
Filed Date | 2007-07-12 |
United States Patent
Application |
20070161768 |
Kind Code |
A1 |
Odaka; Hidetoshi ; et
al. |
July 12, 2007 |
Method for producing hydrolyzable silicon group-containing
oxyalkylene polymer and curing composition thereof
Abstract
The problem of the invention is to efficiently produce a
hydrolyzable silicon group-containing oxyalkylene polymer which has
a low viscosity while maintaining a plasticity of a cured product
and which does not contaminate an area around a sealing portion
and/or has no adverse effect on an adhesion. The problem is solved
by a process for producing a hydrolyzable silicon group-containing
oxyalkylene polymer, which comprises using, as a starting material,
an oxyalkylene polymer in which a first oxyalkylene polymer having
at least two active hydrogen groups and a second oxyalkylene
polymer having one active hydrogen group coexist, and converting
the active hydrogen groups to hydrolyzable silicon groups.
Inventors: |
Odaka; Hidetoshi; (Hyogo,
JP) ; Iwakiri; Hiroshi; (Hyogo, JP) |
Correspondence
Address: |
BRINKS HOFER GILSON & LIONE
P.O. BOX 10395
CHICAGO
IL
60610
US
|
Family ID: |
34823916 |
Appl. No.: |
10/585243 |
Filed: |
January 26, 2005 |
PCT Filed: |
January 26, 2005 |
PCT NO: |
PCT/JP05/01023 |
371 Date: |
July 12, 2006 |
Current U.S.
Class: |
528/25 ;
525/474 |
Current CPC
Class: |
C08G 65/336 20130101;
C08L 71/02 20130101 |
Class at
Publication: |
528/025 ;
525/474 |
International
Class: |
C08L 83/00 20060101
C08L083/00; C08G 77/00 20060101 C08G077/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 30, 2004 |
JP |
2004-024169 |
Claims
1. A process for producing a hydrolyzable silicon group-containing
oxyalkylene polymer, which comprises using, as a starting material,
an oxyalkylene polymer in which a first oxyalkylene polymer having
at least two active hydrogen groups and a second oxyalkylene
polymer having one active hydrogen group coexist, and converting
the active hydrogen groups to hydrolyzable silicon groups.
2. The process for producing the hydrolyzable silicon
group-containing oxyalkylene polymer according to claim 1, wherein
a GPC (gel permeation chromatography) peak top molecular weight of
the second oxyalkylene polymer starting material is not more than
0.6 times a GPC peak top molecular weight of the first oxyalkylene
polymer starting material.
3. The process for producing the hydrolyzable silicon
group-containing oxyalkylene polymer according to claim 1 or 2,
wherein a viscosity of the oxyalkylene polymer starting material in
which the first and second oxyalkylene polymers coexist is at most
3/4 of a viscosity of the first oxyalkylene polymer starting
material.
4. The process for producing the hydrolyzable silicon
group-containing oxyalkylene polymer according to any one of claims
1 to 3, wherein an oxyalkylene polymer in which 100 parts by weight
of the first oxyalkylene polymer and 300 parts by weight or less of
the second oxyalkylene polymer coexist is used as a starting
material.
5. The process for producing the hydrolyzable silicon
group-containing oxyalkylene polymer according to any one of claims
1 to 4, wherein the oxyalkylene polymer starting material in which
the first and second oxyalkylene polymers coexist is obtained by
reacting the first initiator having at least two active hydrogen
groups with an alkylene oxide in the presence of a catalyst to form
the first oxyalkylene polymer, then adding the second initiator
having one active hydrogen group and further reacting the alkylene
oxide to form the second oxyalkylene polymer.
6. The process for producing the hydrolyzable silicon
group-containing oxyalkylene polymer according to claim 5, wherein
a feed rate of the alkylene oxide per molar amount of the second
initiator after addition of the second initiator is not more than
0.6 times a feed rate of the alkylene oxide per molar amount of the
first initiator before addition of the second initiator.
7. The process for producing the hydrolyzable silicon
group-containing oxyalkylene polymer according to any one of claims
1 to 4, wherein the oxyalkylene polymer starting material in which
the first and second oxyalkylene polymers coexist is obtained by
causing the first and second initiators to coexist and then
reacting these initiators with the alkylene oxide in the presence
of a catalyst.
8. The process for producing the hydrolyzable silicon
group-containing oxyalkylene polymer according to any one of claims
1 to 7, wherein the second oxyalkylene polymer starting material is
produced from a second initiator represented by formula 1.
R.sup.1--OH formula 1 (wherein R.sup.1 is a monovalent organic
group free from an unsaturated group and containing at least one
selected from the group consisting of carbon, hydrogen, oxygen and
nitrogen as a constituent atom.)
9. The process for producing the hydrolyzable silicon
group-containing oxyalkylene polymer according to any one of claims
5 to 8, wherein the catalyst is a double metal cyanide complex
catalyst.
10. The process for producing the hydrolyzable silicon
group-containing oxyalkylene polymer according to any one of claims
1 to 9, which comprises a step of converting the active hydrogen
group of the oxyalkylene polymer to a group represented by formula
2. --O--R.sup.2 formula 2 (wherein R.sup.2 is a monovalent organic
group having an unsaturated bond and containing at least one
selected from the group consisting of carbon, hydrogen, oxygen and
nitrogen as a constituent atom.)
11. The process for producing the hydrolyzable silicon
group-containing oxyalkylene polymer according to claim 10, wherein
after the active hydrogen group of the oxyalkylene polymer is
converted to the group represented by formula 2, the hydrolyzable
silicon group is introduced. --O--R.sup.2 formula 2 (wherein
R.sup.2 is a monovalent organic group having an unsaturated bond
and containing at least one selected from the group consisting of
carbon, hydrogen, oxygen and nitrogen as a constituent atom.)
12. The process for producing the hydrolyzable silicon
group-containing oxyalkylene polymer according to any one of claims
1 to 9, wherein the active hydrogen group of the oxyalkylene
polymer is reacted with a compound represented by formula 3 to
introduce the hydrolyzable silicon group.
R.sub.a-3--SiX.sub.a--R.sup.3NCO formula 3 (wherein R is a
substituted or unsubstituted monovalent organic group having from 1
to 20 carbon atoms, X is a hydrolyzable group, a is 1, 2 or 3, and
R.sup.3 is a substituted or unsubstituted divalent organic group
having from 1 to 20 carbon atoms.)
13. A room temperature-curing composition comprising the
hydrolyzable silicon group-containing oxyalkylene polymer produced
by the process according to any one of claims 1 to 12.
14. The room temperature-curing composition according to claim 13,
in which the room temperature-curing composition is substantially
free from a plasticizer.
Description
TECHNICAL FIELD
[0001] The present invention relates to a curing composition which
can be cured in the presence of moisture and a process for
producing a hydrolyzable silicon group-containing oxyalkylene
polymer which is a starting material thereof.
BACKGROUND ART
[0002] A method in which various compounds having a hydrolyzable
silicon group in the end are cured and used in sealing materials,
adhesives and the like is an industrially useful well-known method.
Of these compounds, a polymer whose main chain is an oxyalkylene in
particular is liquid at room temperature, and a cured product
thereof still keeps a plasticity at a relatively low temperature.
Thus, it has properties which are advantageous for use in sealing
materials, adhesives and the like. Further, a method in which these
hydrolyzable silicon group-containing organic polymers are used in
combination with an epoxy resin or an acrylic resin to improve
strengths, an adhesion and a weatherability is also an industrially
useful well-known method. Examples of such moisture-curing
compounds include moisture-curing compounds having a hydrolyzable
silicon group in the end as described in (Patent Document 1),
(Patent Document 2) and the like.
[0003] With respect to such compounds having the hydrolyzable
silicon group in the end, generally, the higher the molecular
weight, the more the plasticity of the cured products is increased,
but the viscosity of the compounds is raised, which notably worsens
the workability. When the molecular weight of such compounds is
low, the viscosity is decreased, but cured products are poor in
plasticity. For providing the low viscosity while maintaining the
plasticity of cured products, various plasticizers have been so far
used.
[0004] As the plasticizers, aromatic carboxylic acid esters,
aliphatic carboxylic acid esters, glycol esters, phosphoric acid
esters, epoxy plasticizers, chlorinated paraffins and the like have
been used. However, these plasticizers have a migration property.
Accordingly, when they are used as sealing materials and the like,
there are drawbacks such as contamination of an area around a
sealing portion and an adverse effect on an adhesion.
[0005] For solving these problems, a method using, instead of a
plasticizer, an oxyalkylene polymer in which one end of a linear
molecular chain is blocked with an organic group and a hydrolyzable
silicon group is provided in the other end (Patent Document 3), a
method using a combination of a high-molecular-weight oxyalkylene
polymer having a high content of a hydrolyzable silicon group per
molecule and a low-molecular-weight oxyalkylene polymer having a
low content of a hydrolyzable silicon group per molecule (Patent
Document 4), a method using a combination of a
high-molecular-weight oxyalkylene polymer having a hydrolyzable
silicon group content of 50% or more per terminal group and an
oxyalkylene polymer having a hydrolyzable silicon group content of
less than 50% per terminal group (Patent Document 5) and the like
have been proposed.
[0006] These oxyalkylene polymers with the low content of the
hydrolyzable silicon group per molecule which are used instead of
the plasticizer are synthesized from an oxyalkylene polymer having
an active hydrogen group such as a hydroxyl group in the end
resulting from the polymerization in the presence of a catalyst
such as an alkali metal catalyst, a metal porphyrin catalyst, a
double metal cyanide complex catalyst or a compound catalyst having
a p=N bond. Among them, a double metal cyanide complex catalyst is
preferably used, because when propylene oxide is used as an
alkylene oxide in particular in producing an oxyalkylene polymer
with the catalyst, an unsaturated mono-ol is less byproduced during
polymerization, and a high-molecular-weight oxyalkylene polymer,
having a narrow distribution of molecular weight, which cannot be
obtained with an alkali metal catalyst is provided.
[0007] However, an oxyalkylene polymer with a low content of a
hydrolyzable silicon group per molecule, which is used instead of a
plasticizer, has been so far produced by converting an active
hydrogen group such as a hydroxyl group to a hydrolyzable silicon
group, separately from an oxyalkylene polymer with a high content
of a hydrolyzable silicon group per molecule. Later, it has been
used instead of a plasticizer by being added to a relatively
high-molecular-weight oxyalkylene polymer with a high content of a
hydrolyzable silicon group per molecule. That is, a relatively
high-molecular-weight oxyalkylene polymer with a high content of a
hydrolyzable silicon group per molecule and an oxyalkylene polymer
with a low content of a hydrolyzable silicon group per molecule
which is used instead of a plasticizer have been produced
separately, making a production process intricate.
[0008] Patent Document 1: JP-A-3-72527
[0009] Patent Document 2: JP-A-3-47825
[0010] Patent Document 3: JP-A-4-57850
[0011] Patent Document 4: JP-A-5-59267
[0012] Patent Document 5: JP-A-9-95609
DISCLOSURE OF THE INVENTION
Problems that the Invention is to Solve
[0013] Accordingly, an efficient process for producing a
hydrolyzable silicon group-containing oxyalkylene polymer which has
a low viscosity while maintaining a plasticity of a cured product
and which does not contaminate an area around a sealing portion and
has no adverse effect on an adhesion has been studied, and the
invention has been consequently made.
MEANS FOR SOLVING THE PROBLEMS
[0014] That is, the invention is a process for producing a
hydrolyzable silicon group-containing oxyalkylene polymer, which
comprises using, as a starting material, an oxyalkylene polymer in
which a first oxyalkylene polymer having at least two active
hydrogen groups and a second oxyalkylene polymer having one active
hydrogen group coexist, and converting the active hydrogen groups
to hydrolyzable silicon groups.
EFFECT OF THE INVENTION
[0015] According to the invention, a hydrolyzable silicon
group-containing oxyalkylene polymer which has a low viscosity
while maintaining a plasticity of a cured product and which does
not contaminate an area around a sealing portion and has no adverse
effect on an adhesion can be produced efficiently.
BEST MODE FOR CARRYING OUT THE INVENTION
[0016] In the process for producing the hydrolyzable silicon
group-containing oxyalkylene polymer in the invention, at least two
types of oxyalkylene polymers are used as starting materials.
[0017] The first oxyalkylene polymer starting material is an
oxyalkylene polymer having at least two active hydrogen groups, and
the second oxyalkylene polymer starting material is an oxyalkylene
polymer having one active hydrogen group.
[0018] A number average molecular weight of the first oxyalkylene
polymer is preferably 4,000 or more per active hydrogen group. When
it is less than 4,000, an elongation of the cured product of the
hydrolyzable silicon group-containing oxyalkylene polymer might be
decreased. The number average molecular weight is more preferably
5,000 or more, especially preferably 7,000 or more.
[0019] On the other hand, it is preferable that the molecular
weight of the second oxyalkylene polymer is not more than 0.6 time
the GPC (gel permeation chromatography) peak top molecular weight
of the first oxyalkylene polymer. When it is more than 0.6 time,
the effect of lowering the viscosity might be decreased. This
molecular weight is more preferably at most 0.5 time, especially
preferably at most 0.4 time. Meanwhile, when the molecular weight
of the second oxyalkylene polymer is too low, a large amount of a
silicon compound is required in converting the active hydrogen
group to the hydrolyzable silicon group which leads to the increase
in cost. Thus, it is practically preferable that the molecular
weight of the second oxyalkylene polymer is 2,000 or more.
[0020] A viscosity of the second oxyalkylene polymer is preferably
at most 3/4 a viscosity of the polymer in which the first and
second oxyalkylene polymers coexist. When it is more than 3/4, the
effect of decreasing the viscosity is considered to be low.
[0021] It is preferable that the second oxyalkylene polymer
coexists in an amount of 300 parts by weight or less per 100 parts
by weight of the first oxyalkylene polymer. When the amount is more
than 300 parts by weight, the curability of the finally obtained
hydrolyzable silicon group-containing oxyalkylene polymer is
notably decreased, and the polymer might not be cured in some
cases. It is more preferably 200 parts by weight or less,
especially preferably 100 parts by weight or less. However, when it
is too small, the expected effect of decreasing the viscosity is
not obtained. Thus, it is preferably 3 parts by weight or more,
more preferably 5 parts by weight or more, especially preferably 10
parts by weight or more. It is most preferably 20 parts by weight
or more.
[0022] The oxyalkylene polymer which is used as the starting
material in the invention can be produced by polymerizing an
initiator such as a hydroxy compound having at least one hydroxyl
group with an alkylene oxide or the like in the presence of a
catalyst such as an alkali metal catalyst, a metal porphyrin
catalyst (refer to gazettes of JP-A-61-197631 and the like), a
double metal cyanide complex catalyst (refer to gazettes of U.S.
Pat. No. 3,278,457, U.S. Pat. No. 3,278,458, U.S. Pat. No.
3,278,459, U.S. Pat. No. 3,427,256, U.S. Pat. No. 4,055,188, U.S.
Pat. No. 4,721,818 and the like) or a compound catalyst having a
P.dbd.N bond (refer to gazettes of JP-A-11-106500, JP-A-10-36499,
JP-A-11-302371 and the like). Of these catalysts, a double metal
cyanide complex catalyst and a compound catalyst having a P.dbd.N
bond which can provide a high-molecular-weight, colorless
oxyalkylene polymer are preferable, and a double metal cyanide
complex catalyst is especially preferable.
[0023] Examples of the double metal cyanide complex catalyst
include Zn.sub.3[Fe(CN).sub.6].sub.2, Zn.sub.3 [Co
(CN).sub.6].sub.2, Fe[Fe(CN).sub.6], Fe[Co(CN) 6] and the like. A
catalyst having a structure in which Zn.sub.3[Co(CN).sub.6].sub.2
(namely, a zinc hexacyanocobaltate complex) is a catalyst skeleton
and an organic ligand is coordinated is preferable.
[0024] Such a catalyst can be produced by, for example,
coordinating an organic ligand in a reaction product resulting from
a reaction of a metal halide salt with an alkali metal
cyanometalate in water. As the metal of the metal halide salt,
Zn(II) or Fe(II) is preferable, and Zn(II) is especially
preferable. As the metal halide salt, zinc chloride is especially
preferable. As the metal constituting the cyanometalate of the
alkali metal cyanometalate, Co(III) or Fe(III) is preferable, and
Co(III) is especially preferable. As the alkali metal
cyanometalate, potassium hexacyanocobaltate is preferable. As the
organic ligand, alcohol and/or ether are/is preferable. At least
one selected from alcohols such as tert-butyl alcohol, compounds
represented by the following formula 4, ethanol, sec-butyl alcohol,
n-butyl alcohol, isobutyl alcohol, tert-pentyl alcohol, isopentyl
alcohol and isopropyl alcohol and ethers such as ethylene glycol
dimethyl ether (hereinafter referred to as glyme), diglyme
(diethylene glycol dimethyl ether), triglyme (triethylene glycol
dimethyl ether), dioxane and polyether with Mn of from 150 to 5,000
is preferable. Of these, at least one selected from tert-butyl
alcohol, compounds represented by the following formula 4 and glyme
is especially preferable.
R.sup.4--C(CH.sub.3).sub.2(OR.sup.5).sub.nOH formula 4
[0025] (wherein R.sup.4 is a methyl group or an ethyl group,
R.sup.5 is an ethylene group or the ethylene group whose hydrogen
atom is substituted with a methyl group or an ethyl group, and n is
1, 2 or 3.)
[0026] Preferable examples of the compounds represented by formula
4 include ethylene glycol mono-tert-butyl ether, propylene glycol
mono-tert-butyl ether, ethylene glycol mono-tert-pentyl ether and
propylene glycol mono-tert-pentyl ether. Ethylene glycol
mono-tert-butyl ether is especially preferable.
[0027] The double metal cyanide complex catalyst can be produced by
stirring and maturing a catalyst skeleton resulting from a reaction
of the metal halide salt with the alkali metal cyanometalate in the
organic ligand, and then conducting separation by filtration,
washing and drying in a known manner.
[0028] As the initiator, an active hydrogen-containing compound can
be used, and examples thereof include the following: monohydric
primary, secondary and tertiary alcohols such as methanol, ethanol,
propanol, butanol, pentanol, hexanol, heptanol, octanol, nonanol
and decanol; unsaturated group-containing monohydric alcohols such
as allyl alcohol, methallyl alcohol and propenyl alcohol;
unsaturated group-containing monohydric alcohols such as
monoallyletherified compounds or monovinyletherified compounds
obtained by monoallyletherifying or monovinyletherifying ethylene
glycol, diethylene glycol, propylene glycol, dipropylene glycol,
1,3-propanediol, neopentyl glycol, 1,4-butanediol, 1,5-pentanediol,
1,6-hexanediol and 1,4-cyclohexanediol, and saturated monohydric
alcohols obtained bymonoalkyletherifying the same; polyhydric
alcohols such as ethylene glycol, diethylene glycol, propylene
glycol, dipropylene glycol, 1,3-propanediol, neopentyl glycol,
1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol,
1,4-cyclohexanediol, glycerin, diglycerin, trimethylolpropane,
pentaerythritol, glucose, sorbitol, sucrose and methyl glycoside;
alkanolamines such as monoethanolamine, diethanolamine and
triethanolamine; phenol compounds such as bisphenol A, bisphenol F,
bisphenol S, resorcin and hydroquinone; aliphatic amines such as
ethylenediamine, diethylenetriamine and hexamethylenediamine; and
an oxyalkylene polymer obtained by a reaction of the foregoing
initiators with alkylene oxide and having a lower molecular weight
than the hydrolyzable silicon group-containing oxyalkylene polymer
which is a desired product.
[0029] The foregoing initiators may be used either singly or in
combination of two or more. However, as the first initiator used
for polymerization of the first oxyalkylene polymer, a compound
mainly containing at least two active hydrogen groups is
preferable. The first oxyalkylene polymer is a component which is
converted to a hydrolyzable silicon group-containing oxyalkylene
polymer and then cured with moisture or the like to form a rubbery
elastomer. In view of its purpose, a compound mainly containing at
least two active hydrogen groups is preferable.
[0030] Meanwhile, as the second initiator used for polymerization
of the second oxyalkylene polymer, a compound mainly containing one
active hydrogen group is preferable. The second oxyalkylene polymer
has a relatively low molecular weight because it coexists for
decreasing the viscosity of the oxyalkylene polymer. For this
reason, when a compound having two or more active hydrogen groups
is contained in a large amount, a plasticity of the cured product
of the hydrolyzable silicon group-containing oxyalkylene polymer
made from the oxyalkylene polymer in which the first and second
oxyalkylene polymers coexist is decreased, and a hard, brittle
cured product is provided. When an oxyalkylene polymer resulting
from polymerization using a compound containing one active hydrogen
group as a second initiator is used as a starting material, the
plasticity of the cured product of the hydrolyzable silicon
group-containing oxyalkylene polymer is not decreased even after
introduction of the hydrolyzable silicon group and subsequent
curing with moisture or the like. Therefore, a second initiator
used for producing the second oxyalkylene polymer is preferably a
compound mainly containing one active hydrogen group, and it is
especially preferable to use an initiator represented by formula 1.
R.sup.1--OH formula 1
[0031] (wherein R.sup.1 is a monovalent organic group free from an
unsaturated group and containing at least one selected from the
group consisting of carbon, hydrogen, oxygen and nitrogen as a
constituent atom.)
[0032] The amount of the initiator of the second oxyalkylene
polymer is 5 or less in terms of a molar ratio relative to the
amount of the initiator of the first oxyalkylene polymer. When the
amount is more than 5, the curability of the finally obtained
hydrolyzable silicon group-containing oxypropylene polymer is
notably decreased, and it might not be cured in some cases. Its
molar ratio is preferably 3 or less, especially preferably 2 or
less.
[0033] Examples of the alkylene oxide include ethylene oxide,
propylene oxide, 1,2-butylene oxide, 2,3-butylene oxide,
isobutylene oxide, epichlorohydrin, epibromohydrin, methyl glycidyl
ether, allyl glycidyl ether, butyl glycidyl ether, 2-ethylhexylene
glycidyl ether, trifluoropropylene oxide and the like. These may be
used either singly or in combination of two or more. Of these,
propylene oxide is preferable.
[0034] A process for producing the oxyalkylene polymer in which the
first oxyalkylene polymer having at least two active hydrogen
groups and the second oxyalkylene polymer having one active
hydrogen group coexist as starting materials of the invention
includes a process in which the first oxyalkylene polymer is
produced by polymerizing at first and further the second initiator
for the second oxyalkylene polymer is added (post addition process)
and a process in which the first and the second polymerizations are
conducted simultaneously in the presence of both the first and the
second initiators (co-initiation process). The polymerization may
be conducted by either of these processes.
Moreover, a process in which polymerizations are conducted
separately and the resulting polymers are mixed also can be
used.
[0035] In the post addition process, the GPC peak top molecular
weights of the first and second oxyalkylene polymers and their
ratio can freely be determined by changing the timing of adding the
initiator of the second oxyalkylene polymer and the feed rate of
the alkylene oxide. It can be applied as a process for effectively
lowering the viscosity of the oxyalkylene polymer.
[0036] It is preferable that the initiator for the second
oxyalkylene polymer is added after formation of the first
oxyalkylene polymer up to approximately the intended molecular
weight. When initiators different in GPC peak top molecular weight
coexist in the polymerization of the alkylene oxide using the
double metal cyanide complex, there is a characteristic tendency
that the polymerization using the initiator having the lower
molecular weight preferentially proceeds and the polymerization of
the initiator having the higher molecular weight little proceeds.
This tendency continues until the GPC peak top molecular weight
ratio of the oxyalkylene polymers obtained using the initiators
different in molecular weight is close to the ratio of the numbers
of the active hydrogen groups of the initiators, and the molecular
weights of the respective initiators are then increased while
maintaining the very ratio. Accordingly, for freely determining the
GPC peak top molecular weight ratio of the first and second
oxyalkylene polymers, it is preferable that after the first
oxyalkylene polymer is formed to approximately the intended
molecular weight, the initiator of the second oxyalkylene polymer
(namely, the initiator having one active hydrogen group) is
added.
[0037] The molecular weight of the second oxyalkylene polymer can
freely be determined from an amount of an alkylene oxide which is
fed after addition of the initiator of the second oxyalkylene
polymer. The feed rate of the alkylene oxide is not more than 0.6
times the feed rate of the alkylene oxide per molar amount of the
first initiator fed in the polymerization for producing the first
oxyalkylene polymer. When it is more than 0.6 times, the molecular
weight of the second oxyalkylene polymer is increased, therefore it
is undesirable. The feed rate of the alkylene oxide is preferably
at most 0.5 times, especially preferably at most 0.4 times.
[0038] On the other hand, in the co-initiation process, the GPC
peak top molecular ratio of the first and second oxyalkylene
polymers cannot freely be determined. However, since the second
oxyalkylene polymer can be formed along with the first oxyalkylene
polymer, the oxyalkylene polymer in which the second oxyalkylene
polymer high in both the molecular weight and its ratio coexists
can be obtained easily. Since such an oxyalkylene polymer has a
high molecular weight, the effect of decreasing the viscosity is
low, but the amount of the hydrolyzable silicon group to be
introduced is decreased because the number of the molecular end is
decreased, which is economically advantageous. It can be applied as
a process in which the plasticity of the cured product resulting
from curing with moisture or the like after introduction of the
hydrolyzable silicon group can appropriately be imparted.
[0039] The hydrolyzable silicon group-containing oxyalkylene
polymer of the invention is obtained by introducing the
hydrolyzable silicon group into the active hydrogen
group-containing oxyalkylene polymer in a suitable manner.
[0040] As the hydrolyzable silicon group in the invention, a
silicon group which allows hydrolysis with moisture and a
crosslinking reaction can be used, and a generally known
hydrolyzable silicon group is usable.
[0041] For example, a silicon group represented by formula 5 is
available. --SiX.sub.aR.sub.3-a formula 5
[0042] In the formula, R is a substituted or unsubstituted
monovalent organic group having from 1 to 20 carbon atoms, and it
is preferably an alkyl group having 8 or less carbon atoms, a
phenyl group or a fluoroalkyl group. A methyl group, an ethyl
group, a propyl group, a butyl group, a hexyl group, a cyclohexyl
group, a phenyl group and the like are especially preferable.
[0043] X is a hydrolyzable group, and examples thereof include a
halogen atom, an alkoxy group, an acyloxy group, an amide group, an
amino group, an aminooxy group, a ketoximate group and the
like.
[0044] In these groups, the carbon number of the carbon
atom-containing hydrolyzable group is preferably 6 or less,
especially preferably 4 or less. A preferable hydrolyzable group is
a lower alkoxy group having the carbon number of 4 or less. Special
examples thereof can include a methoxy group, an ethoxy group, a
propoxy group, a propenyloxy group and the like. a is 1, 2 or 3,
and 2 or 3 is especially preferable.
[0045] A method in which the silicon group represented by formula 5
is introduced into the oxyalkylene polymer is not particularly
limited. The introduction can be conducted by, for example, the
following methods (A) to (D). When the hydrolyzable silicon group
is introduced by the following method (A) or (D), the polymer is
used by being converted to an unsaturated group-containing
oxyalkylene polymer. In this case, however, an initiator
represented by formula 1 has to be used as the initiator of the
second oxyalkylene polymer having one active hydrogen group.
R.sup.1--OH formula 1
[0046] wherein R.sup.1 is a monovalent organic group free from an
unsaturated group and containing at least one selected from the
group consisting of carbon, hydrogen, oxygen and nitrogen as a
constituent atom.
[0047] When the second oxyalkylene polymer is formed using an
initiator in which R.sup.1 has an unsaturated group and the active
hydrogen group contained in the second oxyalkylene polymer is
converted to an unsaturated group, an oxyalkylene polymer having at
least two unsaturated groups is provided. As a result, the
plasticity of the cured product of the hydrolyzable silicon
group-containing oxyalkylene polymer in the invention which is
obtained by curing with moisture or the like is decreased, and a
hard, brittle cured product is provided.
[0048] Accordingly, when the hydrolyzable silicon group is
introduced by the following method (A) or (D), the initiator
represented by formula 1 should be used as the initiator for the
second oxyalkylene polymer having one active hydrogen group.
[0049] The introduction of the hydrolyzable silicon group by the
method (B) or (C) has a defect that the viscosity tends to be more
increased than the introduction of the hydrolyzable silicon group
by the method (A) or (D) because of the side reaction which
proceeds during the reaction of the active hydrogen group with the
isocyanate compound. When using the oxyalkylene polymer in which
the first and second oxyalkylene polymers having the active
hydrogen groups coexist as starting materials of the invention, it
is possible to decrease the viscosity of the oxyalkylene polymers
having the active hydrogen groups as starting materials, which is
used for effectively decreasing the viscosity of the hydrolyzable
silicon group-containing oxyalkylene polymer.
[0050] (A) Method in which an active hydrogen group contained in an
oxyalkylene polymer is converted to an unsaturated group (formula
2) to form an unsaturated group-containing oxyalkylene polymer
which is then reacted with a hydrosilyl-group compound represented
by formula 6. --O--R.sup.2 formula 2
[0051] wherein R.sup.2 is a monovalent organic group having an
unsaturated bond and containing at least one selected from the
group consisting of carbon, hydrogen, oxygen and nitrogen as a
constituent atom. HSiX.sub.aR.sub.3-a formula 6
[0052] wherein R, X and a are as defined above.
[0053] A method for introducing an unsaturated group as described
herein includes a method in which a compound having an unsaturated
group and a functional group is reacted with an active hydrogen
group of an oxyalkylene polymer and the unsaturated group is
incorporated by forming them via an ether bond, an ester bond, a
urethane bond, a carbonate bond or the like, a method in which an
unsaturated group-containing epoxy compound such as allyl glycidyl
ether is added in polymerizing an alkylene oxide to conduct
copolymerization, whereby an unsaturated group is introduced into a
side chain, and the like.
[0054] (B) Method in which an active hydrogen group contained in an
oxyalkylene polymer is reacted with a compound represented by
formula 3. R.sub.3-a--SiX.sub.a--R.sup.3NCO formula 3
[0055] wherein R, X and a are as defined above, and R.sup.3 is a
substituted or unsubstituted divalent organic group having from 1
to 20 carbon atoms.
[0056] (C) Method in which an active hydrogen group contained in an
oxyalkylene polymer is reacted with a polyisocyanate compound such
as tolylene diisocyanate to convert it to an isocyanate group, and
the isocyanate group is then reacted with a W group of a silicon
compound represented by formula 7. --R.sub.3-a--SiX.sub.a--R.sup.3W
formula 7
[0057] wherein R, R.sup.3, X and a are as defined above, and W is
an active hydrogen-containing group selected from a hydroxyl group,
a carboxyl group, a mercapto group and an amino group (primary or
secondary).
[0058] (D) Method in which an active hydrogen group contained in an
oxyalkylene polymer is converted to an unsaturated group, and the
unsaturated group is reacted with a silicon compound represented by
formula 7 in which W is a mercapto group.
[0059] The composition of the invention can contain various known
curing catalysts, fillers and additives. Further, it can contain
plasticizers and the like as required.
[0060] The content of the hydrolyzable silicon group of the first
and second oxyalkylene polymers is preferably at least 40% and at
most 100%, more preferably at least 50% and at most 100%,
especially preferably at least 60% and at most 100% relative to the
active hydrogen group contained in the oxyalkylene polymer as the
starting material.
[0061] The hydrolyzable silicon group-containing oxyalkylene
polymer obtained by the process of the invention can be formed into
a room temperature-curing composition either as such or by
incorporating various additives.
[0062] As the curing catalyst, hitherto-known catalysts can widely
be used. Specific examples thereof include silanol condensation
catalysts, namely, titanium compounds such as tetrabutyl titanate,
tetrapropyl titanate and titanium tetraacetyl acetonate;
tetravalent tin compounds such as dibutyltindilaurate,
dibutyltinmaleate, dibutyltinphthalate, dibutyltin dioctate,
dibutyltin diethyl hexanoate, dibutyltin dimethyl maleate,
dibutyltin diethyl maleate, dibutyltin dibutyl maleate, dibutyltin
dioctyl maleate, dibutyltin ditridecyl maleate, dibutyltin dibenzyl
maleate, dibutyltin diacetate, dioctyltin diethyl maleate,
dioctyltin dioctyl maleate, dibutyltindimethoxide,
dibutyltindinonylphenoxide, dibutyltin oxide, dibutyltin diacetyl
acetonate, dibutyltin diethyl acetoacetonate and a reaction product
of dibutyltin oxide with a phthalic acid ester; divalent tin
compounds such as tin octanoate, tin naphthenate, tin stearate and
tin versatate; organoaluminum compounds such as aluminum trisacetyl
acetonate, aluminum trisethyl acetoacetate and diisopropoxyaluminum
ethyl acetoacetate; zirconium compounds such as zirconium
tetraacetyl acetonate; lead octanoate; amine compounds such as
butylamine, octylamine, dibutylamine, monoethanolamine,
diethanolamine, triethanolamine, diethylenetriamine,
triethylenetetramine, oleylamine, cyclohexylamine, benzylamine,
diethylaminopropylamine, xylylenediamine, triethylenediamine,
guanidine, diphenylguanidine,
2,4,6-tris(dimethylaminomethyl)phenol, morpholine,
N-methylmorpholine, 2-ethyl-4-methylimidazole and
1,8-diazabicyclo(5,4,0)undecene-7 (DBU) or salts of these amine
compounds and carboxylic acids or the like; low-molecular-weight
polyamide resins obtained from larger amounts of polyamines and
polybasic acids; reaction products of larger amounts of polyamines
with epoxy compounds; and silane coupling agents having an amino
group, such as .gamma.-aminopropyltrimethoxysilane and
N-(.beta.-aminoethyl)aminopropylmethyldimethoxysilane, as well as
known silanol condensation catalysts such as other acid catalysts
and basic catalysts, and the like. These catalysts may be used
either singly or in combination of two or more.
[0063] The use amount of these curing catalysts is preferably from
0.1 to 20 parts by weight per 100 parts by weight of the
oxyalkylene polymer of the invention. When the use amount of the
curing catalysts is too small, the curing rate is decreased, and
the curing reaction does not proceed satisfactorily. Thus, it is
undesirable. Meanwhile, when the use amount of the curing catalyst
is too large, local heat generation or expansion occurs at the time
of curing, and a good cured product is hardly obtained. Thus, it is
undesirable.
[0064] In the curing composition of the invention, a silicon
compound represented by the general formula R.sub.4-aSi (OR) a
(wherein R and a are as defined above) may be incorporated in order
to enhance the activity of condensation catalysts. The silicon
compound is not limited. However, compounds of the general formula
in which R is an aryl group having from 6 to 20 carbon atoms, such
as phenyltrimethoxysilane, phenylmethyldimethoxysilane,
phenyldimethylmethoxysilane, diphenyldimethoxysilane,
diphenyldiethoxysilane and triphenylmethoxysilane, are preferable
because an effect of accelerating the curing reaction of the
composition is great. Especially, diphenyldimethoxysilane and
diphenyldiethoxysilane are preferable because they are less costly
and can easily be procured. The amount of the silicon compound is
preferably from 0.01 to 20 parts by weight, more preferably from
0.1 to 10 parts by weight per 100 parts by weight of the
oxyalkylene polymer of the invention. When the amount of the
silicon compound is below this range, the effect of accelerating
the curing reaction might be decreased. Meanwhile, when the amount
of the silicon compound is above this range, a hardness or a
tensile strength of a cured product might be decreased.
[0065] In the composition of the invention, a silane coupling
agent, a reaction product of a silane coupling agent or a compound
other than the silane coupling agent can be incorporated as an
adhesive agent. Specific examples of the silane coupling agent
include isocyanate group-containing silanes such as
.gamma.-isocyanatopropyltrimethoxysilane,
.gamma.-isocyanatopropyltriethoxysilane,
.gamma.-isocyanatopropylmethyldiethoxysilane and
.gamma.-isocyanatopropylmethyldimethoxysilane; amino
group-containing silanes such as
.gamma.-aminopropyltrimethoxysilane,
.gamma.-aminopropyltriethoxysilane,
.gamma.-aminopropylmethyldimethoxysilane,
.gamma.-aminopropylmethyldiethoxysilane,
.gamma.-(2-aminoethyl)aminopropyltrimethoxysilane,
.gamma.-(2-aminoethyl)aminopropylmethyldimethoxysilane,
.gamma.-(2-aminoethyl)aminopropyltriethoxysilane,
.gamma.-(2-aminoethyl)aminopropylmethyldiethoxysilane,
.gamma.-ureidopropyltrimethoxysilane,
N-phenyl-.gamma.-aminopropyltrimethoxysilane,
N-benzyl-.gamma.-aminopropyltrimethoxysilane and
N-vinylbenzyl-.gamma.-aminopropyltriethoxysilane; mercapto
group-containing silanes such as
.gamma.-mercaptopropyltrimethoxysilane,
.gamma.-mercaptopropyltriethoxysilane,
.gamma.-mercaptopropylmethyldimethoxysilane and
.gamma.-mercaptopropylmethyldiethoxysilane; epoxy group-containing
silanes such as .gamma.-glycidoxypropyltrimethoxysilane,
.gamma.-glycidoxypropyltriethoxysilane,
.gamma.-glycidoxypropylmethyldimethoxysilane,
.beta.-(3,4-epoxycyclohexyl)ethyltrimethoxysilane and
.beta.-(3,4-epoxycyclohexyl)ethyltriethoxysilane; carboxysilanes
such as .beta.-carboxyethyltriethoxysilane,
.beta.-carboxyethylphenylbis(2-methoxyethoxy)silane and
N-.beta.-(carboxymethyl)aminoethyl-.gamma.-aminopropyltrimethoxysilane;
vinyl-based unsaturated group-containing silanes such as
vinyltrimethoxysilane, vinyltriethoxysilane,
.gamma.-methacryloyloxypropylmethyldimethoxysilane and
.gamma.-acryloyloxypropylmethyltriethoxysilane; halogen-containing
silanes such as .gamma.-chloropropyltrimethoxysilane; isocyanurate
silanes such as tris(trimethoxysilyl)isocyanurate; and the like.
Further, amino-modified silyl polymers, silylated amino polymers,
unsaturated aminosilane complexes, phenylamino-long chain-alkyl
silanes, aminosilylated silicones, silylated polyesters and the
like which are derivatives obtained by modifying the same are also
available as the silane coupling agent. The silane coupling agent
of the invention is commonly used in the range of from 0.1 to 20
parts by weight per 100 parts by weight of the oxyalkylene polymer
of the invention. Especially, it is preferable to use the same in
the range of from 0.5 to 10 parts by weight.
[0066] The silane coupling agent incorporated in the curing
composition of the invention shows a marked effect of improving an
adhesion under a non-primer condition or a primer treatment
condition when using it in various adherends, namely, inorganic
materials such as glass, aluminum, stainless steel, zinc, copper
and mortar and organic materials such as polyvinyl chloride,
acrylics, polyesters, polyethylene, polypropylene and
polycarbonates. When it is used under a non-primer condition, the
effect of improving the adhesion to various adherends is
outstanding. Specific examples of materials other than the silane
coupling agent are not particularly limited. For example, epoxy
resins, phenolic resins, sulfur, alkyl titanates, aromatic
polyisocyanates and the like are mentioned. The adhesive-imparting
agent may be used either singly or in combination of two or more.
The adhesion to the adherends can be improved by addition of these
adhesive agents.
[0067] The composition of the invention can contain various
fillers. Examples of the fillers include reinforcing fillers such
as fumed silica, precipitated silica, crystalline silica, fused
silica, dolomite, silicic anhydride, silicic hydride and carbon
black; fillers such as ground calcium carbonate, colloidal calcium
carbonate, magnesium carbonate, diatomaceous earth, calcined clay,
clay, talc, titanium oxide, bentonite, organic bentonite, ferric
oxide, aluminum fine powder, flint powder, zinc oxide, active zinc
oxide, shirasu balloon, glass microballoon, organic microballoon of
a phenol resin or a vinylidene chloride resin, and resin powders,
e.g. PVC powder and PMMA powder; fibrous fillers such as asbestos,
and glass fibers and filaments; and the like. When the filler is
used, the use amount thereof is from 1 to 300 parts by weight,
preferably from 10 to 200 parts by weight per 100 parts by weight
of the oxyalkylene polymer of the invention.
[0068] When it is required to obtain a cured product having a high
strength by the use of these fillers, a filler selected from fumed
silica, precipitated silica, crystalline silica, fused silica,
dolomite, silicic anhydride, silicic hydride, carbon black,
surface-treated finely divided calcium carbonate, calcined clay,
clay and active zinc oxide is preferable. When the filler is used
in the range of from 1 to 200 parts by weight per 100 parts by
weight of the oxyalkylene polymer of the invention, good results
are obtained. When it is required to obtain a cured product having
a low strength and a high break elongation, good results are
obtained by using the filler mainly selected from titanium oxide,
calcium carbonate, magnesium carbonate, talc, ferric oxide, zinc
oxide and shirasu balloon in the range of from 5 to 200 parts by
weight per 100 parts by weight of the oxyalkylene polymer of the
invention. Generally, as the specific surface value of calcium
carbonate is higher, the effect of improving a break strength, a
break elongation and an adhesion of a cured product is increased.
Of course, these fillers may be used either singly or in
combination of two or more. It is possible to use a combination of
calcium carbonates having a particle size of 1.mu. or more, such as
fatty acid-surface-treated colloidal calcium carbonate and
non-surface-treated ground calcium carbonate.
[0069] It is preferable to add organic balloons and inorganic
balloons for improving a workability (thixotropic nature or the
like) of the composition or delustering the surface of the cured
product. These fillers may be surface-treated, and they may be used
either singly or in combination of two or more. For improving the
workability (thixotropic nature or the like), the particle size of
balloons is preferably 0.1 mm or less. For delustering the surface
of the cured product, the particle size is preferably from 5 to 300
.mu.m.
[0070] The composition of the invention is advantageously used in
joints of outer walls of houses, comprising ceramic siding boards
especially. It is preferable that the designing of outer walls and
the designing of sealing materials are well balanced. Especially,
an outer wall having a high-grade touch has been used by
incorporating a sputter coating, a color aggregate or the like.
When the composition of the invention contains a flaky or
particulate material having a diameter of 0.1 mm or more,
preferably from 0.1 to 5.0 mm, a cured product is well-balanced
with such an outer wall having a high-grade touch, and a
weatherability is excellent, so that the excellent composition
which keeps the appearance of the cured product for a long period
of time is provided. When a particulate material is used, a surface
with a rough touch such as a sand-spreading touch or a sandstone
touch is provided. When a flaky material is used, an uneven surface
ascribable to a flaky state is provided.
[0071] When the composition of the invention contains particles of
a cured product for a sealing material, the cured product has an
uneven surface to be able to improve the appearance. A diameter, a
mixing amount and a material of particles of a cured product which
are preferable for a sealing material are as follows as described
in gazette of JP-A-2001-115142. The diameter is from 0.1 mm to 1
mm, preferably from 0.2 to 0.5 mm. The mixing amount is from 5 to
100% by weight, preferably from 20 to 50% by weight in the curing
composition of the invention. Examples of the material may include
a urethane resin, a silicone, a modified silicone, a polysulfide
rubber and the like. The material is not particularly limited, so
long as it is used for a sealing material. A modified-silicone-type
sealing material is preferable.
[0072] In the curing composition of the invention, a property
adjusting agent for adjusting tensile properties of a cured product
formed as required may be incorporated. The property adjusting
agent is not particularly limited. Examples thereof include
alkylalkoxysilanes such as methyltrimethoxysilane,
dimethyldimethoxysilane, trimethylmethoxysilane and
n-propyltrimethoxysilane; alkylisopropenoxysilanes such as
dimethyldiisopropenoxysilane, methyltriisopropenoxysilane and
.gamma.-glycidoxypropylmethyldiisopropenoxysilane, functional
group-containing alkoxysilanes such as
.gamma.-glycidoxypropylmethyldimethoxysilane,
.gamma.-glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane,
vinyldimethylmethoxysilane, .gamma.-aminopropyltrimethoxysilane,
N-(.beta.-aminoethyl)aminopropylmethyldimethoxysilane,
.gamma.-mercaptopropyltrimethoxysilane and
.gamma.-mercaptopropylmethyldimethoxysilane; silicone waxes;
polysiloxanes; and the like. The use of the property adjusting
agents can increase the hardness or conversely decrease the
hardness or exhibit the break elongation when curing the
composition of the invention. The property adjusting agents may be
used either singly or in combination of two or more.
[0073] The property adjusting agent is used in the range of from
0.1 to 20 parts by weight, preferably from 0.5 to 10 parts by
weight per 100 parts by weight of the oxyalkylene polymer in the
invention.
[0074] In the curing composition of the invention, a thixotropic
agent (antisagging agent) may be incorporated as required for
preventing sagging to improve a workability. The antisagging agent
is not particularly limited. Examples thereof include polyamide
waxes, hydrogenated castor oil derivatives, metallic soaps such as
calcium stearate, aluminum stearate and barium stearate, and the
like. These thixotropic agents (antisagging agents) may be used
either singly or in combination of two or more. The thixotropic
agent is used in the range of from 0.1 to 20 parts by weight per
100 parts by weight of the oxyalkylene polymer of the
invention.
[0075] In the composition of the invention, a compound containing
an epoxy group in one molecule can be used. When the epoxy
group-containing compound is used, a restoring property of the
cured product can be increased. Examples of the epoxy
group-containing compound can include compounds such as epoxidized
unsaturated oils, epoxidized unsaturated fatty acid esters,
alicyclic epoxy compounds and epichlorohydrin derivatives, mixtures
thereof and the like. Specific examples thereof include epoxidized
soybean oil, epoxidized linseed oil,
di-(2-ethylhexyl)4,5-epoxycyclohexane-1,2-dicarboxylate (E-PS),
epoxyoctyl stearate, epoxybutyl stearate and the like. Of these,
E-PS is especially preferable. For increasing the restoring
property of the cured product, it is preferable to use a compound
having one epoxy group in a molecule. It is advisable to use the
epoxy compound in the range of from 0.5 to 50 parts by weight per
100 parts by weight of the oxyalkylene polymer of the
invention.
[0076] A photo-curing substance can be used in the composition of
the invention. When the photo-curing substance is used, a film of
the photo-curing substance is formed on a surface of a cured
product, and a stickiness of the cured product or a weatherability
of the cured product can be improved. The photo-curing substance is
one in which a molecular structure is chemically changed by action
of light for a considerably short period of time to allow physical
change such as curing. As this type of the compound, a large number
of compounds including organic monomers, oligomers, resins,
compositions containing the same and the like are known, and
commercially available compounds can be employed. As typical
compounds, unsaturated acrylic compounds, polyvinyl cinnamates,
azide resins and the like can be used. Unsaturated acrylic
compounds include monomers and oligomers having one to several
acrylic or methacrylic unsaturated groups and mixtures thereof.
Examples thereof include monomers such as propylene (butylene or
ethylene) glycol di(meth)acrylate and neopentyl glycol
di(meth)acrylate or oligoesters with a molecular weight of 10,000
or less. Specific examples thereof include special acrylate
(difunctional) Aronix M-210, Aronix M-215, Aronix M-220, Aronix
M-233, Aronix M-240 and Aronix M-245; (trifunctional) Aronix M-305,
Aronix M-309, Aronix M-310, Aronix M-315, Aronix M-320, Aronix
M-325; (polyfunctional) Aronix M-400; and the like. Especially
acrylic functional group-containing compounds are preferable, and
compounds containing on average at least 3 acrylic functional
groups in one molecule are preferable. (Aronixes are all products
of To a Gosei Chemical Industry Co., Ltd.)
[0077] Examples of polyvinyl cinnamates include a photosensitive
resin containing a cinnamoil group as a photosensitive group and
obtained by esterifying polyvinyl alcohol with cinnamic acid, and
numerous polyvinyl cinnamate derivatives. The azide resin is known
as a photosensitive resin containing an azide group as a
photosensitive group. There is usually a rubber photosensitive
solution containing a diazide compound as a photosensitive agent,
and other examples thereof are described in detail in "Kankosei
Jushi" (published Mar. 17, 1972 by Insatsu Gakkai Shuppanbu, pp.
93-, pp. 106- and pp. 117-). These may be used either singly or in
combination, and by addition of a sensitizer as required. When
sensitizers such as ketones and nitro compounds or accelerators
such as amines are added, the effects might be enhanced.
[0078] The use amount of the photo-curing substance is preferably
from 0.01 to 20 parts by weight, more preferably from 0.5 to 10
parts by weight per 100 parts by weight of the oxyalkylene polymer
of the invention. When it is less than 0.01 part by weight, an
effect of increasing a weatherability is low. When it is more than
20 parts by weight, a cured product becomes too hard, which causes
crazing. Thus, these are undesirable.
[0079] An oxygen-curing substance can be used in the composition of
the invention. As the oxygen-curing substance, an unsaturated
compound capable of reacting with oxygen in air can be exemplified,
and it has a function of preventing a stickiness of a surface,
adhesion of a dust to a surface of a cured product or the like by
reacting with oxygen in air to form a cured film near the surface
of the cured product. Specific examples of the oxygen-curing
substance include drying oils typified by tung oil, linseed oil and
the like, various alkyd resins obtained by modifying the said
compounds; acrylic polymers, epoxy resins and silicon resins
modified with drying oils; liquid polymers such as
1,2-polybutadiene, 1,4-polybutadiene and C5-C8 diene polymers
obtained by polymerizing or copolymerizing diene compounds such as
butadiene, chloroprene, isoprene and 1,3-pentadiene, liquid
copolymers such as NBR and SBR obtained by copolymerizing these
diene compounds with copolymerizable monomers such as acrylonitrile
and styrene such that the diene compounds are main component; their
modified products (for example, maleinized products and boiled
oil-modified products), and the like. These may be used either
singly or in combination of two or more. Of these, tung oil and
liquid diene polymers are especially preferable. When a catalyst
that accelerates the oxidative curing reaction or a metal dryer is
used in combination, the effect is sometimes increased. Examples of
the catalyst and the metal dryer include metal salts such as cobalt
naphthenate, lead naphthenate, zirconium naphthenate, cobalt
octanoate and zirconium octanoate, amine compounds and the like.
The oxygen-curing substance is used in an amount of, preferably
from 0.1 to 20 parts by weight, more preferably from 1 to 10 parts
by weight per 100 parts by weight of the oxyalkylene polymer in the
invention. When the use amount is less than 0.1 part by weight, the
contamination is not satisfactorily improved. When it exceeds 20
parts by weight, tensile properties and the like of the cured
product tend to be impaired. As described in gazette of
JP-A-3-160053, it is advisable to use the oxygen-curing substance
in combination with the photo-curing substance.
[0080] An antioxidant can be used in the composition of the
invention. When the antioxidant is used, the weatherability of the
cured product can be increased. Examples of the antioxidant can
include hindered phenol, monophenol, bisphenol and polyphenol
antioxidants. Especially, a hindered phenol antioxidant is
preferable. Likewise, it is possible to use hindered amine light
stabilizers such as Tinubin 622LD, Tinubin 144; CHIMASSORB 944LD
and CHIMASSORB 119FL (all manufactured by Nippon Ciba Geigy K.K.);
MARK LA-57, MARK LA-62, MARK LA-67, MARK LA-63 and MARK LA-68 (all
manufactured by Adeka Argus Chemical Co., Ltd.); and Sanol LS-770,
Sanol LS-765, Sanol LS-292, Sanol LS-2626, Sanol LS-1114 and Sanol
LS-744 (all manufactured by Sankyo Company, Limited). Specific
examples of the antioxidant are also described in gazettes of
JP-A-4-283259 and JP-A-9-194731. The antioxidant is used in an
amount of, preferably from 0.1 to 10 parts by weight, more
preferably from 0.2 to 5 parts by weight per 100 parts by weight of
the oxyalkylene polymer in the invention.
[0081] A light stabilizer can be used in the composition of the
invention. When the light stabilizer is used, photo-oxidative
deterioration of the cured product can be prevented. Examples of
the light stabilizer can include benzotriazole, hindered amine and
benzoate compounds, and the like. Especially, a hindered amine
compound is preferable. The light stabilizer is used in an amount
of, preferably from 0.1 to 10 parts by weight, more preferably from
0.2 to 5 parts by weight per 100 parts by weight of the oxyalkylene
polymer in the invention. Specific examples of the light stabilizer
are also described in gazette of JP-A-9-194731.
[0082] When the photo-curing substance is used together in the
composition of the invention and an unsaturated acrylic compound is
especially employed, it is advisable to use, as described in
gazette of JP-A-5-70531, a tertiary amine-containing hindered amine
light stabilizer as the hindered amine light stabilizer for
improving a storage stability of the composition. Examples of the
tertiary amine-containing hindered amine light stabilizer can
include light stabilizers such as Tinubin 622LD, Tinubin 144 and
CHIMASSORB 119FL (all manufactured by Nippon Ciba Geigy K.K.); MARK
La-57, La-62, La-67 and LA-63 (all manufactured by Adeka Argus
Chemical Co., Ltd.); Sanol LS-765, LS-292, LS-2626, LS-1114 and
LS-744 (all manufactured by Sankyo Company, Limited); and the
like.
[0083] An ultraviolet absorber can be used in the composition of
the invention. When the ultraviolet absorber is used, a
weatherability of the cured product can be increased. Examples of
the ultraviolet absorber can include benzophenone, benzotriazole,
salicylate, substituted tolyl and metal chelate compounds, and the
like. Especially, a benzotriazole compound is preferable. The
ultraviolet absorber is used in an amount of, preferably from 0.1
to 10 parts by weight, more preferably from 0.2 to 5 parts by
weight per 100 parts by weight of the oxyalkylene polymer in the
invention. It is advisable to use a phenol or hindered phenol
antioxidant, a hindered amine light stabilizer and a benzotriazole
ultraviolet absorber in combination.
[0084] The composition of the invention may be used as an elastic
adhesive or the like by addition of an epoxy resin. Examples of the
epoxy resin include epoxidized unsaturated polymers, for example,
flame-retardant epoxy resins such as an epichlorohydrin-bisphenol A
epoxy resin, an epichlorohydrin-bisphenol F epoxy resin and
tetrabromobisphenol A glycidyl ether; a novolak epoxy resin, a
hydrogenated bisphenol A epoxy resin, a glycidyl ether epoxy resin
of a bisphenol A propylene oxide adduct, a p-oxybenzoic acid
glycidyl ether ester epoxy resin, an m-aminophenol epoxy resin, a
diaminodiphenylmethane epoxy resin, a urethane-modified epoxy
resin, various alicyclic epoxy resins, N,N-diglycidylaniline,
N,N-diglycidyl-o-toluidine, triglycidyl isocyanurate, polyalkylene
glycol diglycidyl ether, glycidyl ether of a polyhydric alcohol
such as glycerin, a hydantoin epoxy resin, a petroleum resin and
the like. However, these are not critical, and epoxy resins which
are generally used can be used. Epoxy resins having at least two
epoxy groups in a molecule are preferable because a reactivity is
high in curing and a cured product easily forms a three-dimensional
network. Bisphenol A epoxy resins or novolak epoxy resins are more
preferable. Regarding the use ratio of these epoxy resins and the
oxyalkylene polymer of the invention, the invention oxyalkylene
polymer/epoxy resin weight ratio is in the range of from 100/1 to
1/100. When the invention oxyalkylene polymer/epoxy resin ratio is
less than 1/100, the effect of improving an impact strength or a
toughness of the epoxy resin cured product is hardly obtained. When
the invention oxyalkylene polymer/epoxy resin ratio exceeds 100/1,
strengths of the oxyalkylene polymer cured product are
insufficient. The preferable ratio is not absolutely determined
because it varies with the usage of the curing resin composition or
the like. For example, in case of improving an impact strength, a
flexibility, a toughness, a peel strength and the like of the epoxy
resin cured product, the oxyalkylene polymer of the invention is
used in an amount of, preferably from 1 to 10 parts by weight, more
preferably from 5 to 100 parts by weight per 100 parts by weight of
the epoxy resin. Meanwhile, in case of improving strengths of the
cured product of the invention, the epoxy resin is used in an
amount of, preferably from 1 to 200 parts by weight, more
preferably from 5 to 100 parts by weight per 100 parts by weight of
the oxyalkylene polymer of the invention.
[0085] When the epoxy resin is used, an epoxy resin curing agent
can be used in combination. An usable epoxy resin curing agent is
not particularly limited. A generally used epoxy resin curing agent
can be used. Specific examples thereof can include compounds, for
example, primary and secondary amines such as triethylenetetramine,
tetraethylenepentamine, diethylaminopropylamine,
N-aminoethylpiperidine, m-xylylenediamine, m-phenylenediamine,
diaminodiphenylmethane, diaminodiphenylsulfone, isophoronediamine,
amine-terminated polyether; tertiary amines such as
2,4,6-tris(dimethylaminomethyl)phenol and tripropylamine and salts
of these tertiary amines; polyamide resins; imidazoles;
dicyanediamides; boron trifluoride complex compounds; carboxylic
anhydrides such as phthalic anhydride, hexahydrophthalic anhydride,
tetrahydrophthalic anhydride, dodecylsuccinic anhydride,
pyrromellitic anhydride and chlorendic anhydride; alcohols;
phenols; carboxylic acids; and aluminum or zirconium diketone
complex compounds. However, these are not critical. The curing
agents may be used either singly or in combination of two or
more.
[0086] When the curing agent of the epoxy resin is used, the use
amount thereof is from 0.1 to 300 parts by weight per 100 parts by
weight of the epoxy resin.
[0087] A ketimine can be used as the curing agent of the epoxy
resin. The ketimine is stably present in the absence of water, and
decomposed into a primary amine and a ketone by water. The
resulting primary amine becomes a curing agent of the epoxy resin
which is cured at room temperature. The use of the ketimine allows
formation of a one-component composition. Such a ketimine can be
obtained by a condensation reaction of an amine compound and a
carbonyl compound.
[0088] In the synthesis of the ketimine, known amine compounds and
carbonyl compounds can be used. For example, as the amine
compounds, it is possible to use diamines such as ethylenediamine,
propylenediamine, trimethylenediamine, tetramethylenediamine,
1,3-diaminobutane, 2,3-diaminobutane, pentamethylenediamine,
2,4-diaminopentane, hexamethylenediamine, p-phenylenediamine and
p,p'-biphenylenediamine; polyvalent amines such as
1,2,3-triaminopropane, triaminobenzene, tris(2-aminoethyl)amine and
tetra(aminomethyl)methane; polyalkylenepolyamines such as
diethylenetriamine, triethylenetriamine and tetraethylenepentamine;
polyoxyalkylene polyamines; aminosilanes such as
.gamma.-aminopropyltriethoxysilane,
N-(.beta.-aminoethyl)-.gamma.-aminopropyltrimethoxysilane and
N-(.beta.-aminoethyl)-.gamma.-aminopropylmethyldimethoxysilane; and
the like. As the carbonyl compounds, it is possible to use
aldehydes such as acetaldehyde, propionaldehyde, n-butyl aldehyde,
isobutyl aldehyde, diethyl acetaldehyde, glyoxal and benzaldehyde;
cyclic ketones such as cyclopentanone, trimethylcyclopentanone,
cyclohexanone and trimethylcyclohexanone; aliphatic ketones such as
acetone, methyl ethyl ketone, methyl propyl ketone, methyl
isopropyl ketone, methyl isobutyl ketone, diethyl ketone, dipropyl
ketone, diisopropyl ketone, dibutyl ketone and diisobutyl ketone;
.beta.-dicarbonyl compounds such as acetylacetone, methyl
acetoacetate, ethyl acetoacetate, dimethyl malonate, diethyl
malonate, methylethyl malonate and dibenzoylmethane; and the
like.
[0089] When an imino group is present in the ketimine, the imino
group may be reacted with styrene oxide, glycidyl ethers such as
butyl glycidyl ether and allyl glycidyl ether, glycidyl esters and
the like. These ketimines may be used either singly or in
combination of two or more. The ketimine is used in an amount of
from 1 to 100 parts by weight per 100 parts by weight of the epoxy
resin, and the use amount thereof varies with the types of the
epoxy resin and the ketimine.
[0090] In the curing composition of the invention, various
additives may be added as required for adjusting properties of the
curing composition or the cured product. Examples of the additives
include a flame retardant, a curing property adjusting agent, a
radical initiator, a metallic inactive agent, an antiozonant, a
phosphorus peroxide decomposing agent, a lubricant, a pigment, a
foaming agent, a solvent, a mildewproofing agent and the like.
These additives may be used either singly or in combination of two
or more. Specific examples of additives other than those of the
additives listed in the present specification are described in, for
example, gazettes of JP-B-4-69659, JP-B-7-108928, JP-A-63-254149,
JP-A-64-22904 and JP-A-2001-72854.
[0091] The curing composition of the invention may be produced as a
one-component type composition whose components are all mixed in
advance and stored in a sealed condition and cured with moisture in
air after use. It is also possible to produce the curing
composition of the invention as a two-component type composition in
which as a curing agent, components such as a curing catalyst, a
filler, a plasticizer and water are separately mixed, and this
mixture and the polymer composition are mixed before use.
[0092] When the curing composition is a one-component composition,
all the components are previously mixed. Accordingly, it is
preferable that a component containing water is used after previous
dehydrative drying or dehydration is conducted under reduced
pressure while mixing and kneading the components. When the curing
composition is a two-component composition, there is no need to mix
a main component containing the reactive silicon group-containing
polymer with the curing catalyst. Accordingly, even if water is
slightly contained in the mixture, gelation may hardly occur.
However, when a long-term storage stability is required, it is
preferable to conduct dehydrative drying. With respect to the
dehydrative drying method, a heat-drying method is advantageous in
case of a powdery solid product, and a vacuum dehydration method or
a dehydration method using synthetic zeolite, activated alumina,
silica gel or the like is advantageous in case of a liquid product.
It is also possible to conduct dehydration by incorporating a small
amount of an isocyanate compound to react an isocyanate group with
water. In addition to such a dehydrative drying method, the storage
stability is further improved by adding lower alcohols such as
methanol and ethanol, and alkoxysilane compounds such as
n-propyltrimethoxysilane, vinyltrimethoxysilane,
vinylmethyldimethoxysilane,
.gamma.-mercaptopropylmethyldimethoxysilane,
.gamma.-mercaptopropylmethyldiethoxysilane and
.gamma.-glycidoxypropyltrimethoxysilane.
[0093] The use amount of the dehydrating agent, especially the
silicon compound capable of reacting with water, such as
vinyltrimethoxysilane, is from 0.1 to 20 parts by weight,
preferably from 0.5 to 10 parts by weight per 100 parts by weight
of the oxyalkylene polymer of the invention.
[0094] The curing composition of the invention is especially useful
as elastic sealants and adhesives and can be used as sealants and
adhesives of buildings, ships, automobiles, roads and the like. It
is useful as construction sealants requiring non-contamination of a
paint or non-contamination of an area around a joint when coating a
paint on a surface in particular. It is especially useful as
sealants for siding board joint or sealants for stone joint.
Further, since it can be adhered to wide-ranging substrates such as
glasses, porcelains, wood, metals and resin molded articles, it is
available as various types of adhesive compositions. It can be used
as a starting material for usual adhesives and contact adhesives.
Still further, it is useful as food packaging materials, casting
rubber materials, templating materials and paints.
EXAMPLE
[0095] The invention is illustrated below by referring to Example.
However, the invention is not limited by the Example. Incidentally,
in case of a hydroxyl group-containing oxyalkylene polymer, the
number average molecular weight is measured as follows. Assuming
the end structure is composed of a hydroxyl group and an
unsaturated group, the amount of the hydroxyl group is measured
according to JIS K 1557, and the amount of the unsaturated group
according to JIS K 0070. The number average molecular weight is
defined as a molecular weight measured in consideration of the end
number of the initiator. A GPC (gel permeation chromatography) peak
top molecular weight (hereinafter referred to as GPCMP) and a
molecular weight distribution (Mw/Mn) were determined on
polystyrene equivalent basis value measured with a GPC analyzer
using tetrahydrofuran as a solvent. Using a regression correlation
of the GPC peak top molecular weight and the number average
molecular weight is obtained in advance, the number average
molecular weight can be estimated. A viscosity was measured at
23.degree. C. using an E-type viscometer.
Example 1
[0096] <Synthesis of an Oxyalkylene Polymer>
[0097] 50 g of polyoxypropylenediol having a number average
molecular weight of 2,000 was used as an initiator of a first
oxyalkylene polymer, and reacted with 950 g of propylene oxide
(hereinafter referred to as PO) in the presence of a double metal
cyanide complex catalyst to obtain a first oxyalkylene polymer
having GPCMP of 40,000 and a viscosity of 150 Pas. As an initiator
of a second oxyalkylene polymer, 8 g of butanol was added thereto,
and the mixture was reacted with 315 g of PO to obtain an
oxyalkylene polymer in which the second alkylene polymer having
GPCMP of 4,000 coexisted. The viscosity of the oxyalkylene polymer
(P-1) in which the first oxyalkylene polymer and the second
oxyalkylene polymer coexisted was 72 Pas.
[0098] <Synthesis of a Hydrolyzable Silicon Group-Containing
Oxyalkylene Polymer>
[0099] A 28% methanol solution of sodium methoxide was added to P1
such that sodium was 1.2 mols per mol of a hydroxyl group. After a
reaction of removing methanol was conducted at 130.degree. C. under
reduced pressure, allyl chloride was added in an amount of 1.5 mols
per mol of a hydroxyl group, and the reaction was conducted for 2
hours. An unreacted volatile component was distilled off under
reduced pressure to remove an inorganic salt and the like which
were byproduced for purification to obtain a terminally
allyloxidated polyoxypropylene polymer. By quantification of an
unsaturated group, 95% of a hydroxyl group was found to be
converted to an allyloxy group. 500 g of the resulting terminally
allyloxidated polyoxypropylene polymer was reacted with
methyldimethoxysilane in the presence of a xylene solution of a
divinyltetramethylsiloxane platinum complex (containing 3% by
weight of platinum) at 90.degree. C. for 2 hours to afford a
polyoxypropylene polymer (P-2) in which methyldimethoxysilylpropyl
groups were introduced in 75% of all terminal groups.
[0100] (Conventional Method)
[0101] Conventionally, a hydrolyzable silicon group-containing
first oxyalkylene polymer was singly synthesized by singly
polymerizing a first oxyalkylene polymer having at least two active
hydrogen groups in the presence of a catalyst and then introducing
a hydrolyzable silicon group. Further, a hydrolyzable silicon
group-containing second oxyalkylene polymer was singly synthesized
by singly polymerizing a second oxyalkylene polymer having one
active hydrogen group in the presence of a catalyst and then
introducing a hydrolyzable silicon group. Subsequently, these
polymers were mixed to obtain a hydrolyzable silicon
group-containing oxyalkylene polymer which had a low viscosity
while maintaining a plasticity of a cured product and which did not
contaminate an area around a sealing portion or had no adverse
effect on an adhesion.
* * * * *